Bisphenol-A Plant Yield Enhancement
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Accused Products
Abstract
An improved process is provided for producing bisphenol-A (BPA) comprising steps of (1) contacting benzene and a C3 alkylating agent to produce an alkylation effluent comprising cumene; (2) oxidizing the cumene to produce the corresponding hydroperoxide; (3) cleaving the hydroperoxide to produce product comprising phenol and acetone; (4) reacting acetone with phenol to form a reaction product stream comprising crude bisphenol-A product; (5) distilling the reaction product stream, while sending downstream to a BPA-phenol adduct crystallization and purification step, the resulting concentrated BPA phenolic feed stream; (6) producing BPA-phenol adduct crystals by crystallization of the concentrated BPA phenolic feed stream; (7) separating the BPA-phenol adduct crystals by solid-liquid separation; (8) cracking a stream comprising at least a portion of said final mother liquor to recover a product; and (9) recovering and feeding the phenol product of step (8) to step (4) and/or step (7).
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Citations
45 Claims
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1-31. -31. (canceled)
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32. A process for producing bisphenol-A comprising the steps of:
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(a) reacting acetone with a stoichiometric excess of phenol under acidic conditions to form a reaction product stream comprising crude bisphenol-A product, unreacted phenol, possibly unreacted acetone, water of condensation, and other reaction byproducts; (b) distilling in single or multistage the reaction product stream from step (a) to distill off a volatilized unreacted phenol stream, possibly an unreacted acetone stream, and the water of condensation, while sending downstream to BPA-phenol adduct crystallization and purification steps, said purification step comprising one or more solid-liquid separation and wash steps, the resulting concentrated BPA phenolic feed stream consisting essentially of phenol in which the bisphenol-A and byproducts have been concentrated; (c) producing BPA-phenol adduct crystals by crystallization of the concentrated BPA phenolic feed stream in said crystallization, solid-liquid separation and wash steps with cooling for said crystallization by vaporization of an alkane hydrocarbon or mixture of hydrocarbons containing from 4 to 6 carbons; (d) separating the BPA-phenol adduct crystals by solid-liquid separation and washing same in one or multiple stages with a wash phenol stream which may include at least a portion of the volatilized unreacted phenol stream recovered from step (b), or spent wash or mother liquor from subsequent crystallization, solid-liquid separation, and wash steps, to produce final washed BPA-phenol adduct, final spent wash and final mother liquor; (e) cracking a stream comprising at least a portion of said final mother liquor of step (d) in a reactor with basic catalyst under reaction conditions including a temperature of from about 200 to about 350°
C., a pressure of from about 1.33 to 101.3 kPa-a, a residence time of from about 5 to about 600 minutes and a catalyst concentration of from about 5 to about 1500 wppm, said reaction conditions selected to recover a product comprising from about 60 to about 90 wt. % of said portion of said final mother liquorcracked stream as phenol having a purity level of from about 95 to about 100 wt. %, and from about 10 to about 40 wt. % of said cracked stream as heavy residue byproduct; and(f) recovering and feeding the phenol product of step (e) to step (a) and/or step (d). - View Dependent Claims (33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45)
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Specification